Campaigners have confirmed they are set to extend their protests against the Government's tax on fuel.

Garages across South Wales were today preparing for an explosion of panic-buying by desperate drivers as the UK braces itself for a repeat of the fuel protest chaos in 2000 which brought the country to a standstill.

Demonstrations are now set to be staged across three days - from Wednesday until Friday - with refinery blockades, an M4 go-slow between west Wales to Newport and even disruption at the key port of Dover being threatened.

The lobby has been sparked by the price of petrol, which has reached £1 a litre at many filling stations after rising more than 20 per cent in recent months.

And it could soar even more because of the effect of Hurricane Katrina on the US oil industry.

Campaigners from the Fuel Lobby have given the Government until tomorrow to meet them to discuss their grievances - or face protests. But ministers have discussed plans, including petrol rationing, to deal with any threat to oil supplies. Previously the demonstrations were proposed for Wednesday, but Fuel Lobby spokesman Andrew Spence said: 'The plans have changed now.

'It is on Wednesday, Thursday and Friday in different parts of the country.'

Alan Greene, of the Welsh Less Tax on Fuel Group, said they planned to travel along the M4 from Cross Hands to Magor Services near Newport and back on Friday.

'We just can't keep going,' he said. 'If this keeps on, we may as well put a match to our vehicles.'

A Department of Trade and Industry document entitled 'Downstream Oil Resilience' has laid out what the Government will consider if fuel supplies are hit by protests.

It says: 'Measures... may include a restriction in some form of the amount of fuel a motorist is able to purchase. The Secretary of State may also restrict the hours during which filling stations sell fuel.'